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The objective of this study was to evaluate the phytometric characteristics and chlorophyll index of paiaguás grass (Urochloa brizantha) fertilized with wood ash doses and soil water availability. The experiment was carried out in a randomized complete block in a 5x5 fractional factorial scheme (five doses of wood ash: 0, 8, 16, 24 and 32 g dm-3, and five soil water stresses: 4, 8, 16, 32 and 64 kPa), with four replicates. The experimental design was based on the modified central compound, in which 13 combinations of wood ash doses and soil water availability were studied. Each experimental unit consisted of a pot containing 8.7 dm3 of soil and five plants. Three harvests were performed every 30 days after planting, in a 90-day experimental period. At each harvest, plant height, leaf angle, leaf area, stem diameter, and chlorophyll index (SPAD reading) were evaluated. The best results for the phytometric characteristics and chlorophyll index of paiaguás grass were observed in the wood ash dose of 21 g dm-3. There was a reduction of growth and grass chlorophyll content in the soil water tension of 41.20 kPa.

Among Brazilian soils orders, there are some of it classified as acid soils, which need correction to guarantee crop productivity. Currently, limestone is the most used soil corrective and wood ash has been a sustainable alternative to this process. Thus, the objective was to evaluate the effect of two correctives of soil acidity on an Oxisol collected in the Brazilian Cerrado area using limestone and wood ash and the effect of soil correction on initial growth of cowpea. Two greenhouse experiments were carried out: 1) with limestone, using base saturation levels (V%) of 0, 20, 40, 60 and 80; and 2) wood ash, with doses of 0, 8, 16, 24 and 32 g⋅dm−3, both in five randomized blocks. At 40 days after sowing, it was verified that pH values were within the range considered ideal for soil (pH of 5 to 7), according to the increase of base saturation levels and wood ash doses, but limestone provided faster results. Initial growth of cowpea was positively influenced by soil correction with use of both correctives. Wood ash and limestone increased soil pH to adequate values and resulted in better initial crop development.

The Alfalfa is an important forage for animal feeding, used in breeding of specialized herds due to its high protein content, besides having high palatability and energy value. In this context, the objective of this study was to evaluate the effect of calcium and magnesium ratio in the correction of Oxisol for the cultivation of alfalfa (Medicago sativa L.) cv. Creole. The experiment was conducted in the greenhouse at Federal University of Mato Grosso, Campus Rondonopolis-MT. The experimental design was completely randomized with nine treatments relating about calcium/magnesium nutrients: 0/0; 1/0; 0/1; 3/1; 6/1; 9/1; 12/1; 15/1 and 18/1, with 5 repetitions. The evaluated variables were plant height, number of leaves, number of basal shoots, SPAD index, stem diameter, fresh and shoot dry mass, root dry mass and root volume, soil pHCaCl2 and water use efficiency. The results were submitted to analysis of variance and Scott-knott test (p ? 0.05). Both the first and second cut, plant height was lower (24.76 ± 2.57 and 32.82 ± 13.01 cm, respectively) in absence of fertilizers (0/0) in relation to the other ratios. However, the treatments with Ca and/or Mg did not vary significantly, with a mean of 38.07 ± 2.94 and 51.73 ± 7.43 cm, in the first and second cut, respectively. The shoot dry mass showed similar behavior. Lower mass was observed in absence of Ca/Mg in the first cut (1.12 g DM pot-1) and second cut (1.84 g DM pot-1). In the other relations, it was observed a mean of 2.90 and 4.79 g DM pot-1 between the cuts. Likewise, the production of root was lower in absence of fertilizers (1.66 ± 1.05 g DM pot-1) and the others Ca/Mg ratios did not differ from each other (6.14 ± 1.98 g DM pot-1). The SPAD index there was significant effect only in the first cut between the ratio 0/0 and the others, with a mean of 43.48 ± 2.83 and 48.85 ± 2.19, respectively. In the second cut, SPAD index was 38.47 ± 5.82. Soil pH ranged from 5.87 to 5.31 between the cuts. Alfalfa was low sensitive to calcium and magnesium ratios in soil correction, but responded positively to the plant development with increased base saturation.

Brazil is one of the world&rsquo, s largest producers of beef cattle and dairy products, which requires high forage yield to attend grass-fed animals&rsquo, demand. Among the grass species adopted in the forage production system in Brazil, the Brachiaria genus stands out. This genus comprises nearly 85% of all planted forage area. In general, forage production systems in Brazil are essentially rainfed, and thus susceptible to seasonal soil water stresses. Selecting the suitable Brachiaria cultivar for lands susceptible to periodic waterlogging and dry spells is crucial to enhance forage yield, and consequently, to reduce the environmental footprint of the livestock sector. In this research, we investigated the performance of three recent commercial Brachiaria brizantha cultivars (Piat&atilde, BRS Paiagu&aacute, s, and MG13 Bra&uacute, na) extensively adopted in Brazil&rsquo, s grazing systems subjected to different ranges of soil water potential. For three cutting periods, yield related-variables (e.g., plant height, leaf area, dry biomass, and water use efficiency) were measured. Our results point to the existence of a low drought-resistant trait among cultivars, indicating the need for releasing better-adapted cultivars to cope with reduced soil water availability. All cultivars achieved higher performance at soil water pressure head between &minus, 15 kPa and &minus, 25 kPa, and in general, the cultivar. Piat&atilde, showed slightly superior results to most of the treatments.

In water-controlled environments, because rainfall is one of the primary hydroclimatic forcings, its variability can affect the dynamics of soil water content and other related processes such as soil penetration resistance (PR), plant growth, and food production. The objective of this study was to simulate the relative soil water content (s) and PR year-round considering semi-arid rainfall conditions for different soil classes. An experiment was conducted to obtain relative soil water content (s) and PR data in sandy soil and this information was combined with a data set of four soils from a similar experiment conducted on different soil texture classes. The relative soil water content and PR were simulated at a daily timescale using a stochastic soil water balance model for the five soils. The parameters of the PR-s model can be estimated from the soil texture and bulk density. Under rainfed conditions, there is a short window for tillage (plowing and cultivation) of sandy soils compared with clay soils. During the majority of a typical hydrological year, the PR reaches high values (greater than 5.0 MPa) imposing a moderate to high physical limitation for root growth in sandy soils. In the same soils, limiting PR is reached at s levels very close to the field capacity during the drying process. This indicates that an extra input of water through irrigation may be required during the establishment of crops with a well-developed root system in order to prevent impairments to root growth. The daily PR values modeled over the course of a hydrological year followed a beta distribution with shape parameters (α and β) which were strongly correlated with the frequency of rainfall events during the wet season (λwet). The modeling framework presented here for simulating relative soil water content and soil penetration resistance can be applied to agricultural systems in order to prevent physical limitations on crop growth and to plan tillage management schedules.

Given the potential for commercial exploitation of E. spectabile and aiming to curb predatory extractivism, the development of researches that guide its cultivation becomes relevant. This study aims to evaluate the effects of different substrates and seed positions at sowing on the germination and vigor of seeds from two geographical regions. The experiment design was completely randomized in a 2 x 4 x 2 factorial design (seeds from two geographic regions: i.e., Serra Talhada-PE and Graça-CE, both in Brazil; four substrates: blotting paper, sand, vermiculite and coconut fiber: and two sowing positions: over and in between the substrate). Sowing on blotting paper, sand, vermiculite and coconut fiber, in general, was favorable to germination and germination speed index for seeds from both geographic regions. Sowing in between coconut fiber was detrimental to germination and root development regardless of the seed geographical region. However, sowing in between and over coconut fiber and in between sand favored shoot growth. The best combinations for dry matter production were sowing over paper and sand. The substrates blotting paper, sand, coconut fiber and vermiculite are favorable to E. spectabile seed germination regardless of geographic regions, provided that the sowing is made over the substrates. Dado el potencial para la explotación comercial de E. spectabile y con el objetivo de frenar la extracción depredadora, el desarrollo de la investigación para guiar su cultivo se vuelve relevante. En el presente estudio se evaluó el efecto de diferentes sustratos y posiciones de siembra sobre la germinación y el vigor de semillas oriundas de dos regiones geográficas. Se utilizó un diseño completamente aleatorizado, en arreglo factorial 2 x 4 x 2 (semillas de dos regiones geográficas, es decir, Serra Talhada-PE y Graça-CE, ambas en Brasil; cuatro sustratos: papel secante, arena, vermiculita y fibra de coco; y dos posiciones de siembra: sobre y entre el sustrato). La siembra sobre papel secante, arena, vermiculita y fibra de coco, en general, fue favorable a la germinación ya la velocidad de germinación para las semillas de ambas regiones. La siembra en fibra de coco fue perjudicial para la germinación y el desarrollo radicular, independientemente de la región geográfica de las semillas. Sin embargo, la siembra entre y sobre fibra de coco y en arena favoreció el crecimiento de la parte aérea. Las mejores combinaciones para la producción de masa seca fueron la siembra sobre papel y arena. Los sustratos papel secante, arena, fibra de coco y vermiculita son favorables a la germinación de semillas de E. spectabile, independientemente de las regiones geográficas, siempre que la siembra sea sobre los substratos. Dado o potencial de exploração comercial de E. spectabile e visando coibir o extrativismo predatório, torna-se relevante o desenvolvimento de pesquisas que orientem seu cultivo. Este estudo teve como objetivo avaliar o efeito de diferentes substratos e posições da semente na semeadura sobre a germinação e o vigor de sementes de duas regiões geográficas. O delineamento experimental foi inteiramente casualizado em esquema fatorial 2 x 4 x 2 (sementes de duas regiões geográficas: Serra Talhada-PE e Graça-CE, ambas no Brasil; quatro substratos: papel mata-borrão, areia, vermiculita e fibra de coco; e duas posições de semeadura: sobre e entre o substrato). A semeadura em papel mata-borrão, areia, vermiculita e fibra de coco, em geral, foi favorável a germinação e ao índice de velocidade de germinação das sementes das duas regiões geográficas. A semeadura entre a fibra de coco foi prejudicial à germinação e ao desenvolvimento radicular, independentemente da região geográfica das sementes. No entanto, a semeadura entre e sobre a fibra de coco e entre areia favoreceu o crescimento da parte aérea. As melhores combinações para produção de massa seca foram semear sobre papel e areia. Os substratos, papel mata-borrão, areia, fibra de coco e vermiculita são favoráveis à germinação das sementes de E. spectabile, independentemente das regiões geográficas, desde que a semeadura seja feita sobre os substratos.

Neste trabalho será sustentado que as decisões judiciais, acerca da desapropriação para fins de reforma agrária, devem levar em consideração a preservação ambiental da caatinga no Sertão do Pajeú e partir de um entendimento efetivo da aplicação da função social da propriedade. Utiliza-se, como parâmetros, as sentenças judiciais proferidas nos autos dos processos de desapropriação para fins de reforma agrária das Fazendas FAGUSA e Socorro, a primeira localizada no Município de Serra Talhada e a segunda no Município de Afogados da Ingazeira, ambos situados no Estado de Pernambuco. Distingue-se a degradação da caatinga no Sertão do Pajeú e a relação com a função social da propriedade e o bem ambiental. Defende-se a reforma agrária como instrumento de realização da função social da propriedade na proteção do meio ambiente e como base retórica para dar efetividade e pertinência ao discurso judicial de preservação da caatinga no Sertão do Pajeú pernambucano.

Neste trabalho sera sustentado que as decisoes judiciais, acerca da desapropriacao para fins de reforma agraria, devem levar em consideracao a preservacao ambiental da caatinga no Sertao do Pajeu e partir de um entendimento efetivo da aplicacao da funcao social da propriedade. Utiliza-se, como parâmetros, as sentencas judiciais proferidas nos autos dos processos de desapropriacao para fins de reforma agraria das Fazendas FAGUSA e Socorro, a primeira localizada no Municipio de Serra Talhada e a segunda no Municipio de Afogados da Ingazeira, ambos situados no Estado de Pernambuco. Distingue-se a degradacao da caatinga no Sertao do Pajeu e a relacao com a funcao social da propriedade e o bem ambiental. Defende-se a reforma agraria como instrumento de realizacao da funcao social da propriedade na protecao do meio ambiente e como base retorica para dar efetividade e pertinencia ao discurso judicial de preservacao da caatinga no Sertao do Pajeu pernambucano.

The objective was to verify how differences in the accelerated aging test, traditional method (water) or saturated NaCl solution influence the differentiation of the physiological potential of Encholirium spectabile seeds from two geographic regions of Brazil (Graça-CE and Serra Talhada-PE). The experimental design was completely randomized in a 2 × 2 × 5 factorial scheme, in which two methods (water and saturated NaCl solution), seeds from two geographic regions and five aging periods (0 h, 24 h, 48 h, 72 h and 96 h) were evaluated. Results indicated that seeds from Graça-CE were less vigorous than those from Serra Talhada-PE. However, both aging methods (water and saturated NaCl solution) increased the physiological potential of seeds harvested from Graça-CE. E. spectabile seeds presented different levels of physiological potential by the accelerated aging test.